JoeBlow
16-01-2017, 01:48 PM
For sale is my Discovery 17.5" F4.1 primary mirror. Only used about 3 times under the stars to check collimation. The mirror is very clean from any dust or other marks. The mirror is about 5.5 cm thick.
I previously asked Discovery on what material their mirrors are made from, they replied "quartz or Supremax". I suspect mine is Supremax, however there is no serial number on the mirror to know exactly for sure and if you read below I have found it very difficult to communicate with Discovery.
I will include the secondary mirror for free. It is 107mm x 75mm. It will need cleaning as the camera case it came stored in left marks on the surface.
I'm asking about $2200 negotiable for the mirror.
If interested I will sell the rest of the telescope structure for $350. The structure is in almost new condition except for the issues outlined below.
I'm flexible with the price so don't hesitate to make an offer. It would be nice to know that someone will finally get use of this mirror under the stars.
The mirror and telescope is in the Campbelltown, NSW area. Pickup only.
Some background to why I'm selling:
About 3 years ago I purchased a new 17.5" Discovery PDHQ from the States. The intention was for it to be stored in a permanent location at a private dark site for use. However shortly after it arrived circumstances changed and I decided the Telescope was to big to move without a permanent storage site as originally intended. So a bit over a year ago I tried to sell it while it was still wrapped in it's original boxes, however I didn't get the price I was looking for at the time. Sometime later I decided to put the telescope together and see how I manage with handling it. Thats when I discovered there was some type of problem with the placement of the focuser and/or the secondary mirror, I also suspected the secondary mirror might be slightly too small, however after some research it appears to be at about the limit of the minimum size, but something about it's size still seems not right to me. Because of this issue I could not get the telescope to properly collimate. I then spent almost a year corresponding with OPT and Discovery to try and rectify the problem, but Discovery ignored all requests for assistance. So I have now decided to just try and sell the primary mirror.
I previously asked Discovery on what material their mirrors are made from, they replied "quartz or Supremax". I suspect mine is Supremax, however there is no serial number on the mirror to know exactly for sure and if you read below I have found it very difficult to communicate with Discovery.
I will include the secondary mirror for free. It is 107mm x 75mm. It will need cleaning as the camera case it came stored in left marks on the surface.
I'm asking about $2200 negotiable for the mirror.
If interested I will sell the rest of the telescope structure for $350. The structure is in almost new condition except for the issues outlined below.
I'm flexible with the price so don't hesitate to make an offer. It would be nice to know that someone will finally get use of this mirror under the stars.
The mirror and telescope is in the Campbelltown, NSW area. Pickup only.
Some background to why I'm selling:
About 3 years ago I purchased a new 17.5" Discovery PDHQ from the States. The intention was for it to be stored in a permanent location at a private dark site for use. However shortly after it arrived circumstances changed and I decided the Telescope was to big to move without a permanent storage site as originally intended. So a bit over a year ago I tried to sell it while it was still wrapped in it's original boxes, however I didn't get the price I was looking for at the time. Sometime later I decided to put the telescope together and see how I manage with handling it. Thats when I discovered there was some type of problem with the placement of the focuser and/or the secondary mirror, I also suspected the secondary mirror might be slightly too small, however after some research it appears to be at about the limit of the minimum size, but something about it's size still seems not right to me. Because of this issue I could not get the telescope to properly collimate. I then spent almost a year corresponding with OPT and Discovery to try and rectify the problem, but Discovery ignored all requests for assistance. So I have now decided to just try and sell the primary mirror.